Speed detection methods and devices
AssigneeAsia Optical Co., Inc.
InventorDong Huang
Life of this patent
Estimating the term…
Abstract
A speed detection method. A range finder acquires a specific number of distance measurement samples of an object during a period of time. A new unit of measurement larger than respective movement distances of the object in a first period and a second period is acquired. Rough measured distances D1 and D2 respectively corresponding to the locations of the object in the first period and the second period are calculated by comparing portions of the distance measurement samples corresponding to the first period and the second period utilizing the new unit of measurement. A scope is determined based on the D1 and D2 for filtering the distance measurement samples. The speed of the object is calculated based the filtered distance measurement samples.
Claims19
A speed detection method, implemented in a speed detector comprising a range finder, comprising:
- acquiring a specific number of distance measurement samples of an object during a period of time utilizing the range finder;
- acquiring a new unit of measurement larger than respective movement distances of the object in a first period and a second period;
- calculating rough measured distances D1 and D2 respectively corresponding to the locations of the object in the first period and the second period by comparing portions of the distance measurement samples corresponding to the first period and the second period utilizing the new unit of measurement;
- determining a scope based on the distances D1 and D2 for filtering the distance measurement samples;
- and
- calculating a speed of the object based on the filtered distance measurement samples.
A speed detection method, implemented in a speed detector comprising a range finder, comprising:
- acquiring a specific number of distance measurement samples of an object utilizing the range finder, wherein each of the distance measurement samples comprises a sequence of reflected pulses of a distance measurement laser pulse emitted by the range finder in a received pulse order, each of the reflected pulses corresponds to a distance and is distributed in a planar coordinate system spanned by a time axis and a distance axis, and the time-axis and distance-axis coordinates of each reflected pulse respectively comprise the corresponding received pulse order and distance thereof;
- calculating a rough measured distances D1 and D2 respectively corresponding to the locations of the object in a first period and a second period by sampling portions of the distance measurement samples corresponding to the first period and the second period;
- determining a first line on the planar coordinate system based on the first period, the second period, the distance D1, and the distance D2;
- determining a scope based the first line for filtering the distance measurement samples;
- and
- calculating a speed of the object based on the filtered distance measurement samples.
A speed detector, comprising:
- a range finder acquiring a specific number of distance measurement samples of an object during a period of time using the range finder;
- and
- a processor coupled to the range finder, acquiring a new unit of measurement larger than the movement distances of the object in a first period and a second period respectively, calculating a rough measured distance D1 and D2 respectively corresponding to the locations of the object in the first period and the second period by comparing portions of the distance measurement samples corresponding to the first period and the second period utilizing the new unit of measurement, determining a scope based on the distance D1 and distance D2 for filtering the distance measurement samples, and calculating a speed of the object based on the filtered distance measurement samples.
Dependencies are inferred from the claim text.